Wireless telegraphy.



R. A. FESSENDEN. WIBELESS' TELEGRAPHY. APPLICATION FILED DEG. 14, 1905.

1,U59,665. Patented Apr. 22, 1913.

FIGJ- FIE-L2- WITNESSES:

IMVEIMTOJR M I 1M QUSMMMJI W REGINALD A. FESSENDEN, OF WASHINGTON,DISTRICT OF COLUMBIA, ASSIG-NOR, BY

MESNE ASSIGNMENTS, T0 SAMUEL M. KINTNER, 0F PITTSBURGH, PENNSYL- VANIA,AND HALSEY M. BARRETT, OF BLOOMFIELD, NEW JERSEY,'RECEIVERS.

WIRELESS TELEGRAPHY.

roaches.

Patented Apr. 22, 1 9'1 3.

Serial No. 167,242. Divided and this application filed December 14,

1905. Serial No. 291,736.

T 0 all whom it may concern:

Be it known that I, REGINALD A. FEssnN- DEN, residing at Washington, inthe 'District of Columbia, acitizen of the United States,have inventedcertain new and useful Improvements in Wireless Telegraphy, of which thefollowing is a specification.

The invention described in this case, which is a divisionof applicationSerial No. 167242, filed July 27, 1903, patented Mar. 12, 1912, Number1,020,032, relates to the tuning of antennae by altering the 'capacityof the antennae; it also relates to tuning by connecting one or moremembers of a multiple antenna in electrostatic inductive relation; itfurther relates to the utilization of one or more members of a multipleantenna for sending or receiving and altering an electricalcharacteristic of the sending. or receiving members by one or more ofthe other members of the antenna.

The invention is hereinafter more fully described and claimed.

In the accompanying drawing forming part of this specification, Figures1, and 2 show means for tuning the antennas whether k used for sendingor receiving.

In F i 1,'a method is shown of tuning the antennas by changing thecapacity of the antennae, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11.

12 is a device whereby more or less of the antenna can be connected atwill, and 13 is a coil which may form either the primary of thetransformer in which a receiver is placed, when it is desired toreceive, or the secondary of a transformer whose primary is in a circuitfor producing oscillation when it is desired to send.

Fig. 2, shows an alternative apparatus for accomplishing the sameresults, where 14,

15 and 16 are antennae, any of which may be switched in as desired bythe switch 17 passing over the contacts 18, 19 or 20 and being connectedby the switch 21 so as to send or receive at will, while 22, 23 and 24are wires which may be connected to the ground at will by. the switchmaking contactwith one of the contacts 25, 26, 27 28, 29 and 30 arecapacities of diflerent values andit will be seen that on connecting thewire 22 'to ground, the capacity of the vera multiple antenna,

ticalQl l will be largely increased and similarly with the otherantennae.

Since one or more members of the multiple antenna may be connected atwill, or more capacity otherwise introduced and this changes anelectrical characteristic of the antenna, the invention afi'ordsconvenient means for changing the electrical characteristics of theantenna when alternately using it for receiving and sending. It will beunderstood that ordinarily an aerial should have less capacity andinductance when receiving than when sendin a. Engineer, vol. 37.) Theadv ntages of tuning the antenna by altering the capacity between it andanother conductor, will be recognized by those familiar with the art asuseful for various other purposes.

Having thus described my invention and illustrated its use, what I claimas new and desire to secure by Letters Patent, is the following: a v

1. In apparatus for the transmission of energy by electromagnetic waves,the combination of an antenna and an operating instrument connectedthereto, of several complementary conductors andmeans for alteringthe'capacity of the antenna by employing the influence of difierent.ones of said complementary conductors.

2. Apparatus for the transmission of energy by electromagnetic waves,comprising an operating instrument and means for connecting variousportions of the antenna to the instrument.

3. Apparatus for wireless telegraphy,

comprising a multiple antenna having some of. its members connected toan operating instrument and some of its members connected to ground, andthe grounded members being in electrostatic inductiverelation to theactive radiating or receiving members, substantially as described.

4. In wireless telegraphy apparatus, an antenna consisting of severalconductors and means. to alter the electrical characteristics of some ofthe members acting as r21 diators by connecting to others of themembers, substantially as described.

eral separate conductors and means to alter 5. A multiple antennaconsisting of sev'.

the capacity of some of them by the incutting out some of thewmplementary confluence of others selected, substantially as ductors,substantially as described. 10 described. In testimony whereof, I havehereunto set 6. In Wireless telegraphy, the colnbinamy hand.

5 tion of a multiple antenna, connected to op- REGINALD A. FESSENDEN.

erating instruments complementary con- Witnesses: ductors lnfluencingthe antenna, and meagls GERTRUDE M. KELLEY, for altering the capacity ofthe antenna v JESSIE E. BENT.

